Micro-switch provides many advantages such as smaller size and withstanding depressing for millions of times, thus is widely used on 3C electronic products, home appliances and vehicles. Simply speaking, the micro-switch is a control element to set a circuit ON or OFF. Its structure generally includes a holder and a switch assembly and an operation assembly located in the holder. The switch assembly includes a common terminal, a normal-closed terminal and a normal-open terminal. The operation assembly includes a movable member and a pushbutton. The movable member has one end connected to the common terminal. The pushbutton is moved up and down to allow another end of the movable member to sway between the normal-closed terminal and normal-open terminal to switch different connection and conductive states.
A conventional micro-switch such as R.O.C. patent No. 592380 mainly includes an upper lid and a base. The micro-switch also includes a pushbutton, a first pin, a second pin and a conductive reed fastened to the first pin. The pushbutton is depressible downwards onto one end of the conductive reed so that another end of the conductive reed is swayed downwards to connect to the first pin and second pin to generate a switch signal. While it can provide circuit switch function, it relies merely on the conductive reed to bear the downward pressure and provide an elastic force. After used for a prolonged period of time the reed tends to fatigue because of frequent bending up and down and fracture, and result in failure for switching circuit or sending signals.
To remedy the aforesaid shortcoming, China patent No. CN202110987 discloses a micro-switch. Referring to FIG. 1, it mainly comprises a housing 1, a plurality of conductive terminals 2 located on the housing 1, an elastic element 3, a conductive reed 4 and a pushbutton 5. The conductive reed 4 has a pressed portion 41 to be pressed by the pushbutton 5, a contact portion 42 located between the conductive terminals 2, and two connection ribs 43 to bridge the pressed portion 41 and contact portion 42. The elastic element 3 bridges the conductive reed 4 and conductive terminals 2. The conductive reed 4 is supported by the elastic element 3 in normal conditions. The elastic element 3 provides a bracing force for the conductive reed 4 to prevent it from incurring fatigue and fracturing caused by repetitive up and down bending. Therefore the conductive reed 4 has a longer lifespan and can withstand an increased number of depressing. Although it resolves the problem of easy fatigue and fracturing of the conductive reed mentioned above, it still has the following drawbacks remained to be overcome:
First, its contact portion is movable reciprocally between a normal position and a triggering position to switch different connection and conductive states, hence the conductive reed must be formed at a length to connect the pushbutton and conductive terminals. Nowadays technology industry generally has a very low gross profit margin in doing business, reducing metal consumption of the conductive reed can help to reduce production cost and improve the gross profit margin of products. Moreover, during operation of the micro-switch, the pushbutton presses the pressed portion to make the contact portion to sway downwards. Since the conductive reed is formed at a certain length, the pushbutton has to be pushed by a sufficient force to make the contact portion to sway a sufficient range to switch to and fro to different conductive states. In addition, a high current is frequently generated when the contact portion and conductive terminals are contacted and the high current could cause heat on the contact surface to melt part of the contact portion and stick to the conductive terminals. To separate the contact portion from the conductive terminals to switch different connection and conductive states requires a greater pressing force. As a result, the sensitivity of the micro-switch deteriorates. Hence there are still rooms for improvement on the conventional micro-switch structure, especially in terms of reducing the production cost and switching different conductive states through a smaller force.